Bouncing Back From “Deflategate”

Halfway through the 2015 AFC Championship game between the New England Patriots and Indianapolis Colts, game officials discovered that the Patriots were using underinflated footballs on their offensive snaps. A controversy ensued because the Patriots had actually supplied these balls to the game's referee just hours before kickoff. Athletes and physicists have since agreed that using underinflated footballs gives several unfair advantages to the offensive team. Media outlets have focused their attention on two possible culprits behind the deflationary debacle: either the Patriots had intentionally underinflated their supply of footballs, or the climatic conditions, coupled with the various impacts to which the balls were subjected during the course of the game, had somehow altered the internal air pressure of the balls. This controversy soon became known as “Deflategate” (the moniker makes an obvious connection to the 1970s “Watergate” scandal). The purpose of this article is to bring Deflategate into the laboratory activities of high school and undergraduate introductory physics courses. First, we provide some background information on the actual 2015 AFC Championship game and subsequent media blitz surrounding the controversy. When used in an introductory mechanics class, this information can help students contextualize Deflategate as a real-word application of the material they are learning. Next, we recast the spotlight on Deflategate from its current focus, the ideal gas law, to a new one—namely, the physics of a bouncing ball. We then use this scenario as a motivation for a fun but informative set of experiments that can be carried out using equipment already in most high school or college laboratories. The subsequent data analysis relies on three basic principles: projectile motion, conservation of energy, and linear impulse/momentum. The analysis showcases the application of introductory physics to the world of sports, brings current events into the classroom, and demonstrates how multiple problem-solving strategies can be used to examine different aspects of a single event. Finally, some experimental results are presented and discussed.